Henry edwin coi



May 26, 1931. H. 'E. COLEY MANUFACTURE OF ZINC Original Filed Aug, 8, 1927 L w? We may zm Patented May 26, 1931 UNITED STATES PATENT OFFICE HENRY EDWIN COLEY, OF LONDOIRENGLAIH) MANUFACTURE OF ZINC Original application filed August 8, 1927, Serial No. 211,293, and in Great Britain February, 3, 1927. Divided and this application filed June 10, 1929. Serial No. 369,692.

This invention relates to apparatus for use in the manufacture of zinc by the process described and claimed in my co-pending application Serial No. 211,293 from which the present application has been divided.

An apparatus according to the present invention for use in the manufacture of zinc comprises a reducing chamber, means for heating said chamber to a suitable temperature, means for feeding the material to be reduced into said chamber, means for causing said material to pass through said chamber in the form of a comparatively thin layer, means for conveying a hydrocarbon reducing agent into said layer of material when said material is at its reducing temperature said conveying means being water-cooled and adapted to maintain said reducing agent in a non-decomposed condition until it reaches the heatedmaterial and to then discharge the same so 'as to cause the reducing agent whilst still undecomposed to make actual contact with the heated material and means for drawing off from the reducing chamber the vapours produced by the reduction for cooling.

A suitable apparatus for carrying into effect a process according to the present invention is illustrated in the accompanying drawings which apparatus is designed particularly for the manufacture of zinc and like volatile metals.

In the drawings Fig. 1 is a longitudinal elevation, partly in section, of the apparatus.

Fig. 2 is a similar view taken at right angles to Fig. 1 and illustrating the means for preheating the ore and feeding the same to the main tube.

Fig. 3 is a detail view of the hydrocarbon inlet pipe.

The apparatus illustrated in the drawings comprises a rotatable tube 1 constituting the reducing chamber. This tube which is 45 adapted to be heated preferably externally as by burners and entirely or partly by the burning of the gas produced by the reaction is supported u on rollers 2 which engage circumferential anges 3 on the exterior of the tube. These rollers are preferably of a comparatively large diameter and either the rollers or the flanges may be of increasing width towards one end of the tube to allow for the expansion of the tube.

The tube although sealed to prevent the free ingress of air is so constructed and arranged as to allow for the introduction of the ores or the like at one end and the extraction of the gangue at the other end. The reduced metal passes out with and at the same end of the tube as the gases. 7

The hydrocarbon or hydrocarbon containing body when in the liquid form may be led into the interior of the tube at either end by way of a water cooled pipe 4 which as indicated by the dotted lines extends down the interior of the tube a distance suitable for the effective working of the process. If the hydrocarbon or hydrocarbon containing body is not in the liquid form it may be led into the interior of the tube by means of a water cooled or other artificially cooled conveyor. By this means the hydrocarbon is caused to maintain its original or non-decomposed condition until the same actually comes into contact with the heated ore or the like within the tube 1 when the hydrocarbon undergoes decomposition, yielding products of a highly active reducing nature such as nascent carbon, nascent hydrogen et cetera.

This pi e 4 is surrounded by an outer jacket 5, Fig. 3, through which in the present example a stream of water iscaused to circulate.

The inlet for such cooling water is indicated at 6 and its outlet at 7. By this means the hydrocarbon is caused to maintain its original condition until the same actually comes into contact with the heated ore or the like within the tube 1 when it disintegrates and forms nascent carbon which efi'ects the reduction of the ore or the like to its metal.

The ore or the like before being introduced into the tube 1 is preheated to preferably a reducing temperature. This is effected in the example illustrated by passing the same through a rotating tube 8, see Fig. 2, which is dis osed at right angles to the main tube 1. T e preheated tube 8 is fed from a hopper 9 by means of a suitable conveyor 10 and it 100 discharges the preheated ore into the feed hopper 11 of the main tube 1.

From this hopper 11 the ore is conveyed, by means of the conveyor 12, through the wall of and into the interior of a casing forming one part of the take-off or vapour outlet 13. From the interior of this casing the ore is picked up by means of scoop 14-, mounted upon one end of and revolving with the main tube 1 which is set at a slight declination so that the ore works its way slowly through the tube to the opposite end.

As before described the hydrocarbon containing body may be introduced at the opposite end of the tube to that into which the fresh ore is introduced. As a consequence of this fact and the fact that the ore is preheated to at or about a reducing temperature before it is passed into the reducing tube a reducing process goes on throughout practically the en tire length of the reducing tube. By this means the complete reduction desired is facilitated in that the reducing agent when in a condition of least activity comes into contact with the fresh and. therefore richest ore at the inlet end of the tube whilst the poorest ore which is not affected by the reducing agent in this condition is subjected to the hydrocarbon at or adjacent to the point of its introduction into the reducing tube.

The reduced metal in the form of a vapour passes out of the tube 1 with the gases through the'vapour outlet 13 whilst the gangue is discharged into the receptacle 15 from the bottom of which it is continuously removed by means of the conveyor 16.

It will thus be seen that by means of an apparatus as above described the process is a continuous one, the cold ore being fed into the hopper 9 and the gangue discharged automatically and continuously by the conveyor 16.

Air is excluded from the tube during the process to prevent re-oxidation of the metal and this is eifected by the rovision of gas tight joints at both ends of the tube.

Owing to the temperature at which the joint at the gas take-0d end of the tube is required to work, existing types of joint are unsuitable.

The joint at this end, according to the example illustrated comprises a stationary outer casing 17 forming part of or attached to the inner end of the casting forming the gas takeoff 13. This casing consists of an annular plate 18, and a circumferential flange 19 extending horizontally from the plate and disposed concentric with the aperture in the plate. The plate 18 is bolted or otherwise secured to the gas take-01f casting 13. The corresponding end of the tube 1 is formed with a circumferential flange 20 disposed a short distance in from the end of the tube.

When the apparatus is assembled the gas take-off end of the tube 1 projects through rename the aperture in the plate 18 and the flange 20 on this end of the tube resides within the shrouding formed by the horizontal flange 19. The required gas tight joint is formed by interposing a suitable packing 21 between the opposing faces of the flange 20 on the tube and the plate 18 and applying spring or other pressure to the tube 1 so as to hold the flange 20 hard against the packing and to compensate for expansion of the tube 1.

From experiments so far made I have found that the most suitable packing is a machined block of wrought iron. Such a packing material besides providing a gas tight joint will stand up to the high temperature to which it is normally subjected. Any other suitable metal or alloy of metals may however be used in lieu of the Wrought iron.

From my errperiments in this direction I have found that iron or steel wire, preferably in rope form, conmitutes a suitable packing material which besides providing a gas tight joint stands up to the high temperatures to which it is normally subjected.

The above mentioned pressure is applied in the example illustrated through the medi um of a bell crank lever 22, a spring 23 or springs acting upon one arm of such lever, the other arm applying pressure to a suitable surface 24 on the tube through a roller 25 or other anti-friction device. The pressure thus acts in a direction axial of the tube.

The gangue discharge end of the tube may be supported in any suitable manner so as to exclude air but preferably by means of a hearing having a stufing box 26 and a gland packing 27.

Claims 1. Apparatus for use in the reduction of zinc from its ores comprising a tubular reducing chamber, means for introducing ore continuously into one end of said reducing chamber, means at the opposite end of said reducing chamber for continuously removing the gangue therefrom, means for heating the interior of said reducing chamber, artificially cooled conveying means for carrying a hydrocarbon-into the reducing chamber, said conveying means extending downwards to a position near the inside wall of the chamber so as to maintain the hydrocarbon in a non-dccomposed condition until it reaches the ore, and a vapour outlet situated at the ore inlet end of the reducing chamber for removing from the reducing chamber the vapourous products of the reduction.

2. Apparatus for use in the reduction of zinc from its ores comprising a tubular reducing chamber, means for introducing ore con tinuously into one end of said reducing chamber, means at the opposite end of said reducing chamber for continuously removing the gangue therefrom, means for heating the interior of said reducing chamber, artificially cooled conveying means for carrying a hydroore inlet end of the reducing chamber for removing from the reducing chamber the vapourous products of the reduction.

3. Apparatus for use in the reduction of zinc from its ores comprising a tubular and rotary reducing chamber, sealing means at both ends of said chamber for preventing the free ingress of air, means for introducing ore continuously into one end of said reducing chamber, means at the opposite end of said reducing chamber for'continuously removing the gangue therefrom, means for heating the interior of said reducing chamber artificially cooled conveying means for carrying a hydrocarbon into the reducing chamber adjacent the end from which the gangue is removed, said conveying means extending downwards to a position near the inside wall of the chamber so as to maintain the hydrocarbon in a non-decomposed condition until it reaches the ore, and a vapour outletsituated at the ore inlet end of the reducing chamber for removing from the reducing chamber the vapourous products of the reduction.

4. Apparatus for use in the reduction of zinc from its ores comprising a tubular and rotary reducing chamber, sealingmeans at both ends of said chamber for preventing the free ingress of air, means for introducing ore continuously into one end of said reducing chamber, means at the opposite end of said reducing chamber for removing continuously the gangue therefrom, means for heating the interior of said reducing chamber, a normally inclined water-cooled pipe extending from the gangue discharge end of the reducing chamber downwards to a position near the inside wall of the chamber for the introduction of a liquid hydrocarbon and a vapour outlet situated at the ore inlet end of the reducing chamber for removing from the reducing chamber the vapourous products of the reduction.

5. Apparatus for use in the reduction of zinc from its ores comprising a tubular and rotary reducing chamber, sealing means at both ends of said chamber for preventing the free ingress of air, a further chamber for preheating the ore to be reduced, means for introducing such preheated ore continuously into one end of said reducing chamber, means at the opposite end of said reducing chamber for removing continuously the gangue therefrom, means for heating the interior of said reducing chamber, a normally inclined water-cooled pipe extending from the gangue discharge end of the reducing chamber downwards to a position near the inside wall of the chamber for the introduction of a liquid hydrocarbon and a vapour outlet situated at the ore inlet end of the reducing chamber for removing from the reducing chamber the vapourous products of the reduction.

In testimony whereof I aifix my signature.

HENRY EDWIN COLEY. 

